There is a need for a process by which the structure of a multilayered semiconductor integrated circuit may be found. Current techniques provide only partial information or are excessively time consuming to operate.
One known device which may be used to inspect the surface of a body of semiconductor material is described in U.S. Pat. No. 4,438,332 (Lichtenegger). The Lichtenegger device comprises a scanning electron microscope having an electron beam source, means for focussing the electron beam and for controllably scanning the electron beam over the surface of a body of semiconductor material, a first detector responsive to backscattered electrons from the scanned surface, and processing means operable to derive a representation of the scanned surface from signals received from the first detector. The Lichtenegger device further comprises a number of secondary detectors responsive to secondary electrons emitted by the scanned surface, with the processing means being connectable to receive a signal from any of the secondary detectors.